ArticleCMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne2018
Repeated influenza vaccination for preventing severe and fatal influenza infection in older adults: a multicentre case-control study.
Article in CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 26 papers, 4 of them syntheses that pooled it.
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Who cites it
26 citing papers in PubMed, 4 syntheses or guidelines pooled it.
- The Cost of Seasonal Influenza: A Systematic Literature Review on the Humanistic and Economic Burden of Influenza in Older (≥ 65 Years Old) Adults.Advances in therapy · 2024Pooled it
- High Clinical Burden of Influenza Disease in Adults Aged ≥ 65 Years: Can We Do Better? A Systematic Literature Review.Advances in therapy · 2023Pooled it
- Does repeated influenza vaccination attenuate effectiveness? A systematic review and meta-analysis.The Lancet. Respiratory medicine · 2023Pooled it
- Association between influenza vaccination and SARS-CoV-2 infection and its outcomes: systematic review and meta-analysis.Chinese medical journal · 2022Pooled it
- The Dual Role of Preexisting Immunity in Influenza: Protective Recall Versus Constraint of Novel Responses.Immunological reviews · 2026Review
- Influenza vaccination after advanced acute kidney injury: effects on mortality, cardiovascular events, and pneumonia-a target trial emulation.Hypertension research : official journal of the Japanese Society of Hypertension · 2026Article
- Article
- Impact of Influenza Vaccination on the Burden of Severe Influenza in the Elderly: Spain, 2017-2020.Vaccines · 2023Article
- Adjuvant-attenuated symptom severity of influenza infections in vaccinated children.Infectious medicine · 2022Article
- Review
- Article
- Sex-specific effects of aging on humoral immune responses to repeated influenza vaccination in older adults.NPJ vaccines · 2021Article
- Repeated influenza vaccination and hospitalization outcomes among older patients with cardiovascular or respiratory diseases.Human vaccines & immunotherapeutics · 2021Article
- Influenza Vaccine Effectiveness Against All-Cause Mortality Following Laboratory-Confirmed Influenza in Older Adults, 2010-2011 to 2015-2016 Seasons in Ontario, Canada.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2021Article
- Behavior of hospitalized severe influenza cases according to the outcome variable in Catalonia, Spain, during the 2017-2018 season.Scientific reports · 2021Observational
- Comparison of Clinical Characteristics for Distinguishing COVID-19 From Influenza During the Early Stages in Guangdong, China.Frontiers in medicine · 2021Article
- Article
- Article
- Impact of national influenza vaccination strategy in severe influenza outcomes among the high-risk Portuguese population.BMC public health · 2019Article
- [Influenza].Der Internist · 2019Review
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12 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe effectiveness of repeated vaccination for influenza to prevent severe cases remains unclear. We evaluated the effectiveness of influenza vaccination on preventing admissions to hospital for influenza and reducing disease severity.
methodsWe conducted a case-control study in 20 hospitals in Spain during the 2013/14 and 2014/15 influenza seasons. Community-dwelling adults aged 65 years or older who were admitted to hospital for laboratory-confirmed influenza were matched with inpatient controls by sex, age, hospital and admission date. The effectiveness of vaccination in the current and 3 previous seasons in preventing influenza was estimated for inpatients with nonsevere influenza and for those with severe influenza who were admitted to intensive care units (ICUs) or who died.
resultsWe enrolled 130 inpatients with severe and 598 with nonsevere influenza who were matched to 333 and 1493 controls, respectively. Compared with patients who were unvaccinated in the current and 3 previous seasons, adjusted effectiveness of influenza vaccination in the current and any previous season was 31% (95% confidence interval [CI] 13%-46%) in preventing admission to hospital for nonsevere influenza, 74% (95% CI 42%-88%) in preventing admissions to ICU and 70% (95% CI 34%-87%) in preventing death. Vaccination in the current season only had no significant effect on cases of severe influenza. Among inpatients with influenza, vaccination in the current and any previous season reduced the risk of severe outcomes (adjusted odds ratio 0.45, 95% CI 0.26-0.76).
interpretationAmong older adults, repeated vaccination for influenza was twice as effective in preventing severe influenza compared with nonsevere influenza in patients who were admitted to hospital, which is attributable to the combination of the number of admissions to hospital for influenza that were prevented and reduced disease severity. These results reinforce recommendations for annual vaccination for influenza in older adults.
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